Re: [PATCH v2 2/2] drm/msm/dpu: Fix timeout issues on command mode panels

[AngeloGioacchino Del Regno]

Il 11/12/21 22:57, Marijn Suijten ha scritto:
> On 2021-12-12 00:49:09, Dmitry Baryshkov wrote:
> > On Sun, 12 Dec 2021 at 00:35, Marijn Suijten
> > <marijn.suijten@xxxxxxxxxxxxxx> wrote:
> > > [..]
> > > On this note, does it perhaps make more sense to call the "internal"
> > > _dpu_encoder_phys_cmd_wait_for_idle function directly, instead of going
> > > through the "public" dpu_encoder_phys_cmd_wait_for_tx_complete which
> > > seems solely intended to handle the wait_for_tx_complete callback?
> >
> > Either one would work. The main difference is the error message. Do
> > you want to see it here if the wait times out or not?
>
> I prefer calling _dpu_encoder_phys_cmd_wait_for_idle directly and
> optionally adding our own error message.  IIRC DRM_ERROR prints source
> information such as the function this originated from, and that makes it
> impossible to distinguish between the wait_for_tx_complete callback or
> the invocation through dpu_encoder_phys_cmd_wait_for_commit_done anyway.
>
> - Marijn

I wouldn't be happy to find myself in a situation in which I get strange
display slowness without any print to help me; for this reason, I find
having the print in place useful for debugging of both perf and fault.

Cheers,
- Angelo